1. Field
This disclosure generally relates to damping materials used to absorb or attenuate acoustic and/or mechanical vibrations and deals more particularly with a method and apparatus for automated placement of damping materials on structures.
2. Background
Damping materials are used in a variety of applications to dampen or attenuate acoustic and/or mechanical vibrations in a structure. For example, acoustic dampening materials are commonly used in parts of vehicles to reduce the noise in passenger cabins produced by external sources such as engines and turbulent airflow.
In aircraft applications, patches of viscoelastic material have been added to various parts of an aircraft structure in order to reduce noise and vibration. These patches may be relatively expensive to install, in part due to the hand labor required to fit, cut, and bond the patches to uniquely shaped structures on the aircraft. Moreover, these patches add weight to the aircraft which may reduce operating efficiency since several hundred and even thousands of such patches may be required for a typical commercial aircraft.
More recently, relatively lightweight composite laminates have been devised which may incorporate viscoelastic materials that act to absorb and thereby attenuate vibration in aircraft structures. While these new damping materials have a number of advantages, their widespread use on aircraft structures may be limited because of the time and manual labor required for their installation, particularly where the aircraft structure has a complicated geometry and precise hand placement of the viscoelastic material on or within the lamina of the structure is required.
Accordingly, there is a need for automated placement of damping materials on structures such as aircraft which reduces the need for hand labor to install the material, and which may provide rapid placement of the materials with high placement accuracy.